1. Field of the Invention
The present invention relates to a power test facility system of a train and a testing method of the same.
2. Description of the Background Art
In an electric motor used in a conventional electric train system, a direct current motor having a good starting torque is mainly used. However, since a lifespan of a segment contact point is short, the direct current motor is frequently exchanged. In order to overcome the above problem, an induction motor is used. However, the induction motor has a problem that a starting torque is bad. Generally since a weight occurring in a train connection is higher than an average weight, it is impossible to implement an enough traction power based on only a starting force of an induction motor.
In order to overcome the above problems, a three-phase motor is used. Namely, an inverter is used for a direct current section, and a VVVF CI(Responsive Voltage Responsive Frequency Converter Inverter) is used in an alternating section. A propulsion apparatus is controlled by varying a voltage and frequency.
In the present invention, a propulsion apparatus of a train represents the construction combined with one converter/inverter and two or four traction motors. The train is formed of a M(Motor) car and a T(Trailer) car. A propulsion apparatus is provided in only the M car. The load facility represents a facility for combining a loader inverter and an induction generator.
In order to periodically test whether an instrument power such as a traction power and a breaking power is properly performed during an operation of a propulsion apparatus, a certain test facility is needed for thereby stably and accurately testing an operation of a train.
However, since there is not provided a facility for systematically and accurately testing such a propulsion apparatus in the conventional art, an inverter and a traction motor are separately tested. In addition, the above test is performed using a fixed load facility, so that a reliability with respect to an instrument performance test is bad. In addition, an estimation possibility with respect to a safety and adaptability during an operation of a facility is low, so that various problems may occur.
For example, in the case of a traction motor, since a tested device(device under test) is continuously rotated and is tested by forming an inertia force using a resistance load, an accuracy is decreased. In addition, in the case that a traction inverter is tested, since a load facility is fixed, the test may be performed, not considering a varying real time information such as a train information, track information, etc. which are expected in an actual train section, so that a reliability is decreased with respect to a test result.
FIG. 1 is a view illustrating an arrangement of elements provided in a train. As shown therein, there is provided a propulsion apparatus which is adapted to rotate four wheels provided in a lower portion of an electric rail car as a power is supplied to an electric rail car(here, referred to one car of a train).
The power is supplied to a propulsion apparatus by a collector(Pantograph) through a power cable. The power supplied to the propulsion apparatus is DC 750V˜1500V in the direct current section, and AC 25,000V in the alternating current section. However, the above standard may be changed based on the standards of each country.
Generally, one convertertinverter(C/I) and two or fourth three-phase AC motor are connected to one car. The capacity of the motor is 300KW, 1100KW. W/hen the power is supplied to the train, the DC is changed into the AC through the inverter in the DC section, so that the power is supplied to the AC motor for thereby driving the motor. The wheels of the train are driven by the propulsion power from the motor. In the AC section, the power of 25000V is changed to the DC for thereby dropping the voltage, and the DC is changed into the AC by the inverter for thereby driving the motor.
Before an inverter, converter, motor or generator are installed in an electric rail car, researches are performed for testing the performance based on various methods with respect to the above elements in a certain research center or test institute. For example, the performance of the inverter is measured in the type test, and in the combination test, the converter/inverter is combined with the traction motor for thereby testing a traction power. The load inverter and induction generator are combined, and a load force is tested. In the case of the train operation simulation test, the propulsion apparatus is installed in the train, and a train information and track information are inputted for measuring the power when the trains runs on an actual track. A resistance force is computed in real time and operates as a load with respect to the traction power of the propulsion apparatus. The speed of the train, an acceleration, traction power and breaking power are measured.
In the Korean patent registration publication No. 10-0317558(Publication date: Dec. 24, 2001, applicant: Korea rail road research center) “Power test control method and apparatus for test operation”, it is possible to enhance a reliability of a power test during a train test operation in such a manner that a data related to a railroad car test operation test item is simply and conveniently measured and analyzed using a computer.
However, the above invention is basically directed to test-operating the train and testing an operation of the train. The above invention does not disclose a technology concerning a facility system with respect to the power test for the instruments provided in the train.
In particular, in the conventional art, it is impossible to perform a combination test of a converter and inverter and a traction motor, a combination test of a load inverter and an induction test and a train operation simulation test based on a train information, track information and load. In addition, it is impossible to systemically perform a power test of a train because there is not provided a test facility which is capable of quickly and accurately testing the power of a converter, inverter, motor or generator which is installed in various kinds of trains such as a DC electric rail car, DC light electric train, G& high speed electric train, and KTX high speed electric train.